From: Eric Sandeen <sandeen@redhat.com>
Subject: Re: fsck.ext4 taking months
Date: Mon, 28 Mar 2011 10:07:22 -0500
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To: Christian Brandt <brandtc@psi5.com>
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On 3/27/11 6:28 AM, Christian Brandt wrote:
> Situation: External 500GB drive holds lots of snapshots using lots of
> hard links made by rsync --link-dest. The controller went bad and
> destroyed superblock and directory structures. The drive contains
> roughly a million files and four complete directory-tree-snapshots with
> each roughly a million hardlinks.
> 
> Tried
> 
> e2fsck 1.41.12 (17-May-2010)
>         Benutze EXT2FS Library version 1.41.12, 17-May-2010
> 
> e2fsck 1.41.11 (14-Mar-2010)
>         Benutze EXT2FS Library version 1.41.11, 14-Mar-2010
> 
> Symptoms: fsck.ext4 -y -f takes nearly a month to fix the structures on
> a P4@2,8Ghz, with very little access to the drive and 100% cpu use.

Does that mean very little access to -this- drive or to -any- drive?
IOW, are you swapping madly?

-Eric

> output of fsck looks much like this:
> 
> File ??? (Inode #123456, modify time Wed Jul 22 16:20:23 2009)
>   block Nr. 6144 double block(s), used with four file(s):
>     <filesystem metadata>
>     ??? (Inode #123457, mod time Wed Jul 22 16:20:23 2009)
>     ??? (Inode #123458, mod time Wed Jul 22 16:20:23 2009)
>     ...
> multiply claimed block map? Yes
> 
> Is there an adhoc method of getting my data back faster?
> 
> Is the slow performance with lots of hard links a known issue?
>